1. Field of the Invention
The present invention relates to a trigger operated dispensing device, e.g. a trigger sprayer, for mounting on a storage container. The trigger sprayer includes a pumping mechanism having a trigger, a piston and a pumping chamber for pumping a desired amount of liquid out of the storage container and wherein the trigger is releasably coupled to the piston.
The pumping mechanism operates in two working strokes: a fluid intake stroke and a fluid ejection stroke. The fluid intake stroke sucks liquid out of the container into the pumping chamber. The fluid ejection stroke discharges the fluid from the pumping chamber through a nozzle assembly of the trigger sprayer into the atmosphere. The fluid ejection stroke is carried out by the operator squeezing the trigger and the fluid intake stroke is carried out by a biasing mechanism, such as a spring or spring assembly, of the pumping mechanism.
More specifically, the present invention relates to a trigger-piston connection wherein the trigger and the piston are detachably and movably connected to each other.
2. Description Of The Related Art Including Information Disclosed Under 37 CFR 1.97-1.99
Heretofore, various trigger sprayers have been proposed.
Three examples of previously proposed trigger sprayers having a trigger-piston connection are disclosed in the following patents:
______________________________________ U.S. Pat. No. Patentee ______________________________________ 3,061,202 Tyler 4,606,480 Gazulla 4,624,413 Corsette ______________________________________
The Tyler U.S. Pat. No. 3,061,202 discloses a V-shaped notch or crotch at the outer end of a spring biased piston received in a cylinder in a trigger sprayer. A rounded edge of a cross web in a trigger is received in the notch and moves between the sides of the notch as the trigger is squeezed.
The Gazulla U.S. Pat. No. 4,606,480 discloses a trigger sprayer which uses a vertical pumping system and wherein a trigger is provided with a laterally (horizontally) extending cylindrical shaft which is pressed into a concave molding having an arc greater than a half circle. As the trigger is squeezed, two arms, disposed forkwise and each having a curved end surface, engage and push upwardly a tubular piston.
The Corsette U.S. Pat. No. 4,624,413 discloses a trigger sprayer wherein a piston has an outwardly open central bore which is undercut for snap fitting engagement with a piston rod 30 having a head configured for snap fitting engagement with the undercut of the bore. The piston rod is integrally connected through a web or hinge with a trigger hingedly connected to the body of the trigger sprayer. The web or hinge will bend as the trigger is squeezed.